The study was undertaken to determine the causes of the more frequent pre-term deliveries, fetal and neonatal deaths associated with maternal urinary-tract infections during pregnancy. The combined perinatal mortality rate for eight common placental and fetal disorders was 42 per thousand births in the infected vs. 21 per thousand in the noninfected, owing to a greater mortality from noninfectious placental and fetal disorders in the gestations with the urinary-tract infections (P<0.001). All the mortality excess took place when the urinary-tract infections occurred within 15 days of delivery. Death rates were highest when the urinary-tract infections coexisted with maternal hypertension and acetonuria. Hydramnios, amniotic-fluid bacterial infections and abruptio placentae were responsible for two thirds of the more frequent preterm deliveries in the pregnancies complicated by urinary-tract infections. (N Engl J Med 300:819–823, 1979) THE past two decades have produced many contradictory reports about the effects of maternal urinary-tract infections during pregnancy on the fetus. There have been both claims and denials that such infections increase perinatal mortality rates, increase the frequency of pre-term deliveries and lower infant birth weights for gestational age.1 2 3 4 5 6 7 8 9 10 11 12 These uncertainties are likely to continue until the exact mechanisms by which urinary-tract infections affect the placenta and fetus are discovered. The present study looked for clues to these mechanisms by identifying the placental and fetal disorders associated with the maternal urinary-tract infections. Patients and Methods The Collaborative Perinatal Project of. © 1979, Massachusetts Medical Society. All rights reserved.
